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Untold stories of a game developer

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You’ve practiced and taken all variables into account. You zero in on the target. Finally, through the combination of calculation, instinct and luck… SWISH! Two points!

I believe the popularity of physics in games is due to two things.

Familiarity Physics gameplay allows you to use the instincts you have developed since childhood. You’re using real-world skills to do the impossible in a virtual environment.

It Feels Good It gives you a sense of accomplishment that you only get in physics simulations. The same feeling you get when you successfully shoot a basketball.

Tappy Physics

Being created with Corona SDK and Box 2D, an open source physics engine, Tappy Lander is a game that pits your piloting skills against your biggest enemy, gravity. The physics engine handles the forces of your thrust in a semi-weightless environment splendidly. It also handles collisions so that your ship explodes only when it feels like it should, and the falling debris bounces around on the ground realistically. Although some of the collision code is built from scratch, most of it relies on the Box 2D engine. Friction, bouncy-ness and gravity of each planet varies and is all controlled by Box 2D.

Emergent Gameplay

One of the joys of physics is that you get all kinds of fun and sometimes unexpected results. The first time I landed in the prototype I noticed a little bounce. At first I thought “Wow, that looked realistic and cool”. My imagination sparked, I quickly then asked. “What if you get extra points for a higher bounce”?

Tricks

Both the slide and the bounce trick (seen here in the Tappy Lander Trailer) was made possible and inspired by side effects of the physics code. Some planets have less friction than others, allowing a super long slide if you come in at the right angle with enough thrust. Other planets are softer and bouncier, allowing for a super high bounce. Tricks yield lots of points when done correctly but are very risky and easy to botch.

Sliding A proper slide requires that you touchdown onto the landing pad and slide off of it into the planet terrain. If you touchdown on the planet terrain at any speed your rocket explodes. Oftentimes when attempting a slide you will either overshoot the target or skip off the target and hit the ground.

Bouncing If gravity is low and you come across a soft planet, conditions are perfect for a high bounce. Remember, however, one of the fundamental rules of landing: hitting the target too hard results in an explosion-so be careful! A 2000 point bounce unlocks the “Megabounce!” achievement and its possible to get an even bigger “Gigabounce!”

That’s how physics work in Tappy Lander and now you know the origin of the trick system! Next… I’m not sure what I’ll talk about yet!

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